Vertical Diffusion in a Stratified Cooling Lake
Publication: Journal of Hydraulic Engineering
Volume 113, Issue 3
Abstract
Lake Anna, a reservoir of 3,900 ha and 21 m maximum depth, provides cooling water for the two‐unit North Anna Nuclear Power Station in Virginia. Using the flux‐gradient method, vertical diffusivities in the lower layers of Lake Anna are computed from seven years of temperature data dating back to before plant operation. Results indicate strong dependence of vertical mixing on condenser flow rate with average summertime diffusivities below the surface layer ranging from for conditions of two‐unit operation and from for conditions of zero to one unit operation. Vertical diffusion is parameterized as a calibrated function of condenser flow rate, wind speed, and a characteristic vertical density difference. A numerical model employing this parameterization gives good agreement between measured and predicted vertical temperature profiles during separate validation tests.
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References
1.
Adams, E. E., and Wells, S. A., “Field Measurements on Side Arms of Lake Anna, Va.,” Journal of Hydraulic Engineering, ASCE, Vol. 110, No. 6, 1984, pp. 773–793.
2.
Barton, J. L., “Water Quality Characteristics of a Thermally‐Influenced Virginia Reservoir, Lake Anna, Related to Eurythermic and Mesothermic Species Preferenda,” Proceedings North American Lake Management Society, held Oct., 1984, in McAfee, N.J., 1985.
3.
Fischer, H. B., et al., Mixing in Inland and Coastal Waters, Academic Press, New York, N.Y., 1979.
4.
French, R. H., “Transfer Coefficients in Stratified Channel Flow,” Journal of the Hydraulics Division, ASCE, Vol. 105, No. 9, Sept., 1979, pp. 1087–1101.
5.
Henderson‐Sellers, B., “Role of Eddy Diffusivity in Thermocline Formation,” Journal of the Environmental Engineering Division, ASCE, Vol. 102, No. 3, 1976, pp. 517–531.
6.
Ho, E., and Adams, E. E., “Final Calibration of the Cooling Lake Model for North Anna Power Station,” Technical Report No. 295, R. M. Parsons Laboratory for Water Resources and Hydrodynamics, MIT, 1984.
7.
Holley, E. R., Harleman, D. R. F., and Fischer, H. B., “Dispersion in Homogeneous Estuary Flow,” Journal of the Hydraulics Division, ASCE, Vol. 96, No. 8, 1970, pp. 1691–1709.
8.
Jassby, A., and Powell, T., “Vertical Patterns of Eddy Diffusion during Stratification in Castle Lake, California,” Limnology and Oceanography, Vol. 20, No. 4, 1975, pp. 530–543.
9.
Jirka, G. H., et al., “Analysis of Cooling Effectiveness and Transient Long‐Term Simulations of a Cooling Lake with Application to the North Anna Power Station,” Technical Report No. 232, Ralph M. Parsons Laboratory for Water Resources and Hydrodynamics, MIT, 1977.
10.
Jirka, G. H., and Harleman, D. R. F., “Cooling Impoundments: Classification and Analysis,” Journal of the Energy Division, ASCE, Vol. 105, No. 2, Aug., 1979, pp. 291–309.
11.
McCormick, M. J., and Scavia, D., “Calculation of Vertical Profiles of Lake‐Average Temperature and Diffusivity in Lakes Ontario and Washington,” Water Resources Research, Vol. 17, No. 2, 1981, pp. 305–310.
12.
Munk, W. H., and Anderson, E. R., “Notes on a Theory of the Thermocline,” Journal of Marine Research, Vol. 7, No. 3, 1948, pp. 276–295.
13.
Pareek, N. K., Discussion of “Role of Eddy Diffusivity in Thermocline Formation,” by B. Henderson‐Sellers, Journal of the Environmental Engineering Division, ASCE, Vol. 103, No. 4, 1977, pp. 749–750.
14.
Sundaram, T. R., and Rehm, R. G., “The Seasonal Thermal Structure of Deep Temperate Lakes,” Tellus, Vol. 25, No. 2, 1973, pp. 157–167.
15.
Tetra Tech, Inc., “Assessment Methodology for New Cooling Lakes, Vol. 3: Limnological and Fisheries Data and Bibliography,” EPRI Report No. EA‐2059, Vol. 3, 1981.
16.
Turner, J. S., Buoyancy Effects in Fluids, Cambridge University Press, Cambridge, U.K., 1973.
17.
Walters, R. A., Carey, G. F., and Winter, D. F., “Temperature Computation for Temperate Lakes,” Applied Mathematical Modeling, Vol. 2, 1978, pp. 41–48.
18.
Wells, S. A., “A Three‐Dimensional Field Evaluation and Analysis of Water Quality in Two Reservoirs,” thesis presented to Tennessee Technological University at Cookeville, Tenn., in 1980, in partial fulfillment of the requirements for the degree of Master of Science.
19.
Wells, S. A., Adams, E. E., and Harleman, D. R. F., “Calibration and Verification of the Cooling Lake Model for North Anna Power Station during the Period July 1978–Sept., 1981,” Technical Report No. 272, R. M. Parsons Laboratory for Water Resources and Hydrodynamics, MIT, 1982.
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Published In
Journal of Hydraulic Engineering
Volume 113 • Issue 3 • March 1987
Pages: 293 - 307
Copyright
Copyright © 1987 ASCE.
History
Published online: Mar 1, 1987
Published in print: Mar 1987
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